


Years After The End

by letussin



Category: Undertale (Video Game)
Genre: Incest, M/M, Monster Heat, dub-con
Language: English
Status: Completed
Published: 2016-01-24
Updated: 2016-01-24
Packaged: 2018-05-16 00:29:47
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,934
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/5806237
Author URL: https://archiveofourown.org/users/letussin/pseuds/letussin
Summary: <blockquote class="userstuff">
              <p>Five Years after the True Pacifist End, Sans body is finally going into heat. The only one around is Papyrus.</p>
            </blockquote>





	Years After The End

**Author's Note:**

> Monster heats AU where heats start off really gentle before getting into the raunchy stuff, and some mini headcannons about what goes on after the end of the true pacifist runs. And about Papyrus’s hands. Uh, this is more emotional porn then anything? My first real attempt at porn, so hopefully it's okay.
> 
> http://fontcest.tumblr.com/post/136026479536/years-after-the-end

Five years was a long time without resets.

Sans leaned against the telescope, staring up at the ceiling. A foot tapped against the floor, restlessness settling in his bones. Something just didn’t seem right. Papyrus and all of their friends had pulled together to let Sans and Papyrus vanish for a few months to a remote mountain and go star-studying. Well, to be more exact, it was supposed to be just Sans, but Papyrus had been dragged along by the desperate pleading of a Sans who didn’t want to face being in a house on his own for several months. Silence was not really Sans friend, it brought too many bad memories.

The thought of Papyrus stilled Sans foot. He pushed away from the telescope, and started wandering down to where Papyrus was ‘waiting’ for night to fall. Then Sans would usually point out the different constellations and planets, to Papyrus’s wondering joy.

Papyrus was sitting on the couch watching Mettaton’s newest television show. Sans flopped over the edge of the grey couch, more then a little put out by how long the couch was, keeping him from being able to go right into Papyrus’s lap. The green couch at home was really good for that. Papyrus had the nerve to laugh at him as he squirmed the rest of the way over, resting his head against a ribcage.

The battle-body was replaced by a soft hoodie that Toriel had sewn for them a few Christmas’s back. Sans had been sad to see his hard work into the costume had gone, but at least this way he wasn’t tormented with brief glimpses of Papyrus’s rib cage and hip bones. Sans nuzzled into the hoodie, and Papyrus draped an arm around him.

“You lazybones! It is barely noon yet!”

“Gotta get my rest somehow,” Sans murmured, as he sank further into Papyrus’s side.

It felt so good, just lying here.

There would be no one coming to check on them for at least a week, as isolated as they were far up into the mountains. Night time was the best time, the sky ablaze with stars. Papyrus was well-versed in amusing himself outside in forests, even if he wasn’t used to forests that weren’t full of fellow monsters.

But the thought of just them being there uninterrupted filled Sans with a quiet little joy. He would never stop his brother from being a ‘Mascot’ of Monsters to Humanity, and he didn’t resent the way it had taken time from them both. But it didn’t keep him from being just the tiniest bit sad to come home to an empty house.

These few months were meant to reconnect, and Sans enjoyed every second of it.

He especially enjoyed these quiet moments where neither one of them were ‘busy’ and they could just relax on the couch without worry.

Papyrus shifted, and Sans let himself fall into Papyrus’s lap, staring up at the long, thin skull. Papyrus’s scarf fluttered with him, baring a long stretch of neck bones that caught his attention more then it should.

Should? Why shouldn't it?

Sans reached up, short fingers stroking the exposed vertebra. Papyrus shivered at the unexpected touch, but didn’t stop him. Instead he craned his head down, the angle awkward, but giving Sans the ability to reach more of it. Long arms ‘trapped’ him, warmth flowing through his bones.

His fingers stroked where the human had in a number of timelines punched or cut Papyrus’s head right off. Those bones had always been weak- that was why Papyrus had the scarf.

Papyrus made a noise as Sans dragged his thumb along the thin, far too delicate bones yet again. “Sans?”

At Papyrus’s quiet voice, confused and… oh.

Sans said quietly, “I should get moving.”

He knew why, all of a sudden, he had been feeling so happy these past few days- his heat was finally beginning. Years of living through various resets, of being stressed that everything was going to end, and start, lingering stress over standing in an empty hallway for weeks, days, months, fighting for (too, it should be too) death over and over again-

His body finally found it safe enough to go into a heat. And he could feel the fire beginning to course through his bones, promising it to be a long, hard one. Where else could he feel safe but in an isolated building where the only other living being that existed was one of the very few monsters he truly cared about? But he shouldn’t corrupt his brother that way. He couldn’t-

Sans felt himself go cold as Papyrus let go, mind blanking on the reason why. “I- Sans?” Papyrus sounded so confused, and that was right, Sans needed to push up, get himself into his bedroom. He needed to find a way to soundproof it too, because-

“Sans, are you okay? You’ve been acting odd these past few days. I was hoping you’d tell me on your own, and we wouldn’t go back to acting like we were in Snowdin, but…”

At the reminder of their old home, the heat flared, and wound a little more insistently around Sans bones. Telling him, promising him, that he could cheer up his brother right here. Reassure him. Touch him, and push back lightly to run his thumb across the pelvic bone to coax out a quiet moan. They’d be closer then they had ever been if Sans just reached out and kissed him.

Sans trembled slightly, unable to convince himself to walk away, but resisting the urge to get closer. Papyrus hesitated for a few seconds, before boldly reaching out to draw Sans into another hug. Sans knew how bad the heat had sunk in, because it was like little miniature electric bolts coursing through his bones. It just felt so good.

He needed to think of some reason not too do this. Sans glanced down to red gloved hands, and tried his best to summon the usual painful feelings whenever he saw them. It wasn’t working- instead, almost of their own accord, his fingers were gently curling around Papyrus’s. He tugged the gloves off, to reveal long, once graceful bones.

Sans ran his knuckles across the blackened bones, feeling the uneven bubbliness there even after years of healing. Back when he couldn’t control his blasters, and Papyrus had approached him anyways, hands burned by Sans magic, and he wasn’t scared of him- why-

“Sans, I love you too much to be really scared of you.” Papyrus murmured into his neck, and Sans shivered at the contact. He bit back a whimper at the word love- Papyrus didn’t mean it the way Sans dreamed he meant it.

His heat reminded him that these burnt, damaged hands were the signs of Papyrus’s devotion. He should show his devotion back and use his tongue and fingers, his very soul, to worship the body before him. Use every bit of knowledge he had to coax moans and gasps, let Papyrus drown in the intense pleasure and knowledge that he was really the greatest.

Sans lifted a hand to his mouth, gently kissing it. Papyrus made a noise, but didn’t pull his hand away. Sans eyes flickered towards his, and stayed there. _The second Papyrus showed fear,_ he promised himself, _I’ll pull back._ He pressed another light, gentle kiss to Papyrus’s phalanges, where the most burnt bones lay. He could remember the fear he had felt, the anger and self-despair at himself when he realized he was hurting his precious (annoying then, his stupid, younger self) brother.

And with the fear, came the feeling of the utmost gratefulness, love, and devotion he had back then when Papyrus smiled through pained tears to say-

“I love you.”

Sans voice was shaking. His heat was pounding through his bones, and he couldn’t hold back anymore as he pressed kiss after kiss against Papyrus’s hands. The metacarpus’s, the mate, the capitale, the trapezium, trapezoid, lunate, scaphoid-

There was still no fear in Papyrus’s eyes, only confusion. One hand reached out to touch Sans cheekbone, and Sans said again, begging almost, “I love you Papyrus.”

“I love you too Sans.” Papyrus repeated, and shivered as Sans fingers tightened against the ulna and raidus.

“I- Not the way- I can’t- I want too-“

“It’s okay Sans,” Papyrus soothed, and reached out again to gently run his fingers across the top of Sans head in what he knew distantly what was supposed to be a platonic gesture. Sans leaned into the touch, fingers still curled up against the wrists. “Whatever you need, it’s fine.”

It wasn’t fine, the back of Sans mind babbled, almost drowned out. The bigger part of him was drowning in the warmth and happiness at being granted access to everything he could ever want- everything he had ever dreamed of. “I- just promise me that you’ll tell me if you don’t like any of it, okay?”

Papyrus nodded, still confused. Sans was pretty confident in his ability to make Papyrus happy, and he was especially confident he’d be able to make Papyrus feel good. At least-

“Do you need me to do something?” Papyrus questioned, brightly grinning. “You’ve been restless quite a bit lately. I could make something or-“

Sans shook his head, pulling Papyrus lightly to get up. Papyrus pretty much leapt to his feet, his boundless energy bursting through. Sans grin was a little wider then normal as he said, “Shortcut!” He pushed backwards, letting magic wrap around them both to fall straight into his bed.

Papyrus bounced a little, arms automatically wrapping around Sans. Sans felt contentment and little pin-prickling excitement grow within him at the motion. “Sans! How?! How do you manage these sorts of things-?!” His voice was cut off as Sans pressed bony lips against Papyrus’s skull.

There was another moment of silence- Papyrus had long given up questioning how Sans had lips. Papyrus shifted beneath him, fingers curling into the back of his neck. Sans reached down, pulling up Papyrus’s sweater to get at bare bones underneath. “Oh, are we uph-!”

Papyrus broke off in a surprised, but pleased noise as Sans curled his fingers through the ribs, sliding and skimming across them lightly, teasingly. Followed them down, curving straight into the sensitive vertebrae. He trickled his fingers down the spinal cord, pressing it firmly into the bed. “Mmm, Sans, I- that- feels so good-“

Magic sparked and spun like the snowflakes they had lived among for so long, twirling through Sans fingers and forming at certain points along Papyrus’s body. The heat was sinking into him too, filling him with the indescribable feeling to touch, feel-

Darkened phalanges attempted to reciprocate, but were quickly caught. Sans shook his head, trembling ever so slightly. That could come later, he just wanted to explore the body he’d dreamed about for years. “N-Not yet Papyrus, j-just lemme do you first.”

“B-but Sans! That would be most disgraceful to not make you feel so good back- I- I just want you to feel good as well.” Papyrus pleaded, sending another bolt of lust and love down Sans spine. His brother loved him so much, and it was really messing with his heat- his heat demanded he take the lead, show Papyrus, who he knew didn’t have any experience, the ride of his life. To worship the body of one that had been devoted to him. On the other hand-

Papyrus whimpered softly, a low, quiet, pained sound as Sans fingers tightened too hard on his hands.

Sans let go immediately, magic shuddering in anger and distress to cause his brother(mate) pain, of any kind. How could he? Just what kind of mate- Sans almost pulled away, as Papyrus caught his hoodie instead. He stopped as Papyrus tugged, babbling desperately, “Sans, please I want- I want to make you feel good. To see you smiling happily.”

Sans stood still, as Papyrus tugged him lightly, magic still there. Still flurrying around both of them, lightly, for the taking. Still so open and trusting. He could feel his own magic, intertwining to nuzzle up against it. He could feel Papyrus’s gentle love, overflowing with warmth and trust.

Sans swallowed hard- he couldn’t take the chance and hurt Papyrus anymore, but he couldn’t find it in himself to pull away from this warm forgiveness that intoxicated more then any alcohol. Papyrus reached down, curling his fingers against stained shorts where his cock was rock hard and begging for attention he didn’t want it to have.

Penance.

Sans pulled away, felt Papyrus’s magic shudder and cling, as his brother’s face fell. Felt a yawning, gaping hole, as he picked up Papyrus’s scarf from where it had fluttered down onto the messy floor. He knew how much Papyrus trusted him, could feel it in the way Papyrus’s magic skated against his own. So when he gently took Papyrus by the hands again, and started winding the scarf around wrists, threading the fabric between radius and ulna, he didn’t feel any protest, just a simple curiosity. “Sans?” Sans swirled the fabric around the burnt bones, pressing a gentle kiss to each before covering it with the soft fabric.

He pulled it tight- not too tight. Just enough to keep Papyrus from wiggling loose, before tying the scarf-wrapped hands to the headboard. Papyrus kneeled on the bed, still mostly dressed like some delicious gift waiting to be unwrapped. Magic spun through the air, dizzying and loud. Papyrus pouted, “Sans, I can’t touch you like this.”

“Don’t need to Papyrus, tonight it’s gonna be all about you.” Sans promised softly, because no matter how much he wanted, needed, first things first- prove to Papyrus that he could be gentle. That he wouldn’t hurt Papyrus any further. Then he would have his pleasure.

Magic buzzed at his fingertips, curled around his body like a heavy tentacle, or a overeager dog, straining to let loose. Slowly, calmly, he told it, they’d hurt Papyrus before, but not this time. He squashed down his own magic, and knelt instead at Papyrus’s back. Reverently he hooked his fingers around the iliac crest, a magic created tongue coming out to trace a wet, hot, sloppy trail across the sactum. The moment he hit the coccyx, Papyrus moaned, legs trembling, almost giving out. His magic flared, sensually twining around Sans, the feedback of pleasure so clear Sans could practically feel it himself.

Sans shuffled forward a little, settling in a little deeper to Papyrus’s body as he tugged futilely against the makeshift bonds whimpering softly, “S-Sans, p-please! Don’t stop!”

Sans wasn’t about to begin to ignore that plea. With a devilish little smile, his head bobbed, tongue slipping against the coccyx once more as fingers curled around the half formed cock. His magic nudged and helped shape Papyrus’s, showing him the way. It was longer, skinnier then his short and thick one- it was quite perfect honestly.

Sans fingers hummed with slightly repressed magic, as he stroked down the cock, feeling each shudder and shake. He pressed his face against Papyrus’s back, eyeing the soul magic pressed up against Papyrus’s ribs, a bright orange heart beating away faithfully.

His magic reached out to gently caress it, twining around it in a sensual kiss that had Papyrus collapsing around him from the overwhelming sensations of pleasure in both body and magic. “S-Saaaaaaaaans!” As Papyrus’s wail, Sans quietly groaned into his backside, cock throbbing angrily despite it being ignored. “Aaaaah!”

Sans pressed a kiss against the back of the neck, where he knew it had been cut off, magic coming out to stroke against Papyrus’s soul, tracing the outer edge of the heart. Hips bucked against his, grinding into his cock. “P-Please Sans, d-don’t fall asleep!”

He wasn’t about to fall asleep right now for anything. Not when Papyrus ground against him, little electric bolts going everywhere. Not with his soul beating and melting against his ribcage, attempting to join with Papyrus’s.

Sans shifted, one hand reaching up to gently caress the heart, the other hand firmly stroking down on the magical cock- it didn’t take long for Papyrus to come, shaking and crying out as he did so. The orange heart and cock spurted at the same time, Papyrus’s soul singing through Sans bones in delight. Sans lifted his fingers, tasting the sweet, tangy flavor on his hands. Papyrus shook for a few seconds, as Sans heat settled for a moment, curling in satisfaction.

Papyrus moaned as Sans hands dipped to wander across his ribs. “We-We’re going to keep on going?” Papyrus stuttered out, hazy and soft.

“You can take it.” Sans encouraged softly, pressing soft kisses against Papyrus’s ribs, “We’ve barely even begun.” Their heat was going to last a long, long time, hopefully without resets interrupting it.

“Nyehehehe, sounds like you have a very good idea there Sans.” Papyrus chuckled weakly, already beginning to recover. “What’s next on the list? My turn?”

“Tomorrow,” Sans promised, fingers snaking out to stroke against the sacrum, teasing the coccyx gently. But just for now, Sans was going to worship this body before him.

Whatever Papyrus was going to say was lost in a pleased moan as Sans sucked at the coccyx, fingers and magic twining around his soul. Papyrus shuddered and shook, opening up and molding himself to his body like a puzzle piece in a puzzle. Sans soul and cock pounded away, straining eagerly for the chance to to ravenge the more then eager partner. To mark Papyrus as his, at least for this reset.

Sans really couldn’t wait for tomorrow.


End file.
